Super-junction metal oxide semiconductor field effect transistors (MOSFETs) comprise a drift region made up of both N-type and P-type regions. Super-junction MOSFETs critically depend on maintaining a definite charge relation between the N and P regions in the drift regions. In general, plate type structures in a drift region show less manufacturing variation in volume, and hence less variation in total charge, in comparison to pillar type structures, e.g., with a round or oval cross section. Accordingly, devices comprising plate type structures in a drift region generally present improved control of a desired charge relation, in comparison to pillar type structures. For this reason, plate type structures may be preferred over pillar type structures for a drift region of a super-junction MOSFET.
However, plate type regions have a directional asymmetry in the sense that in one direction the plates are floating, and in the other, perpendicular, dimension they assume source potential at very low currents. This characteristic requires development of a termination scheme within the constraints of charge balance requirements.